Experience with bisoprolol in long-QT1 and long-QT2 syndrome

J Interv Card Electrophysiol. 2016 Nov;47(2):163-170. doi: 10.1007/s10840-016-0161-2. Epub 2016 Jul 9.

Abstract

Background: The protective effect of beta-blockers in patients with inherited Long-QT syndrome is well established. Recent reports have suggested that beta-blockers are not equally effective in Long-QT (LQT). Bisoprolol is an attractive candidate for use in LQT because of its cardioselective properties and favorable side-effect profile.

Methods: We performed a retrospective cohort study of 114 consecutive patients with gene-positive Long-QT syndrome type 1 (LQT1) or Long-QT syndrome type 2 (LQT2) treated with bisoprolol, nadolol or atenolol with a total of 580 person-years of follow-up. Electrocardiogram (ECG) parameters and cardiac events during follow-up were compared. In addition, exercise treadmill testing was performed in bisoprolol-treated patients.

Results: Fifty-nine patients were treated with bisoprolol, 39 with atenolol and 16 with nadolol. Overall, 59 % were females and 62 % had LQT1. Baseline heart rate and corrected QT (QTc) interval were similar between the groups. QTc shortening was observed in individuals on bisoprolol (ΔQTc -5 ± 31 ms; p = 0.049) and nadolol (ΔQTc -13 ± 16 ms; p = 0.02) but not on atenolol (ΔQTc +9 ± 24 ms; p = 0.16). Median follow-up was similar for bisoprolol and nadolol (3 years), but longer for atenolol (6 years; p = 0.03); one cardiac event occurred in the bisoprolol group (1.7 %) and two events occurred in the atenolol group (5.1 %; p = 0.45), whereas none occurred in nadolol-treated patients. Beta-blocker efficacy was not affected by the underlying genotype. The antiadrenergic effect of bisoprolol correlated with the reduction of peak heart rates at exercise testing.

Conclusions: Bisoprolol treatment results in QTc shortening in gene-positive LQT1 and LQT2 patients and is well tolerated during long-term administration. The equivalence of bisoprolol for protection from ventricular arrhythmia in LQT patients compared to established beta-blockers remains unknown. Further large-scale studies are required.

Keywords: Beta-blocker; Bisoprolol; Channelopathy; Inherited arrhythmia; LQT1; LQT2; Long-QT.

Publication types

  • Multicenter Study
  • Video-Audio Media

MeSH terms

  • Adrenergic beta-1 Receptor Antagonists
  • Adult
  • Bisoprolol / administration & dosage*
  • Canada
  • Cardiotonic Agents / administration & dosage
  • Cohort Studies
  • Electrocardiography / drug effects*
  • Female
  • Heart Rate / drug effects
  • Humans
  • Long QT Syndrome / diagnosis
  • Long QT Syndrome / drug therapy*
  • Male
  • Retrospective Studies
  • Romano-Ward Syndrome / diagnosis*
  • Romano-Ward Syndrome / drug therapy*
  • Treatment Outcome

Substances

  • Adrenergic beta-1 Receptor Antagonists
  • Cardiotonic Agents
  • Bisoprolol

Supplementary concepts

  • Long Qt Syndrome 2